package com.daoeping.servlet;

import java.io.File;
import java.io.IOException;
import java.io.PrintWriter;
import java.text.SimpleDateFormat;
import java.util.Arrays;
import java.util.Date;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Random;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.commons.fileupload.FileItem;
import org.apache.commons.fileupload.FileItemFactory;
import org.apache.commons.fileupload.FileUploadException;
import org.apache.commons.fileupload.disk.DiskFileItemFactory;
import org.apache.commons.fileupload.servlet.ServletFileUpload;
import org.json.simple.JSONObject;

/**
 * Servlet implementation class UploadJson
 */
public class UploadJsonServlet extends HttpServlet {
	private static final long serialVersionUID = 1L;
       
    /**
     * @see HttpServlet#HttpServlet()
     */
    public UploadJsonServlet() {
        super();
        // TODO Auto-generated constructor stub
    }

	/**
	 * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
	 */
	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
	}

	/**
	 * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
	 */
	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		//文件保存目录路径
				String savePath = this.getServletContext().getRealPath("/") + "upload/";
				//文件保存目录URL
				String saveUrl  = request.getContextPath() + "/upload/";
				//定义允许上传的文件扩展名
				HashMap<String, String> extMap = new HashMap<String, String>();
				extMap.put("image", "gif,jpg,jpeg,png,bmp");
				extMap.put("flash", "swf,flv");
				extMap.put("media", "swf,flv,mp3,wav,wma,wmv,mid,avi,mpg,asf,rm,rmvb");
				extMap.put("file", "doc,docx,xls,xlsx,ppt,htm,html,txt,zip,rar,gz,bz2");
				PrintWriter out = response.getWriter();
				//最大文件大小
				long maxSize = 1000000;
				response.setContentType("text/html; charset=UTF-8");

				if(!ServletFileUpload.isMultipartContent(request)){
					out.println(getError("请选择文件。"));
					return;
				}
				//检查目录
				File uploadDir = new File(savePath);
				if(!uploadDir.isDirectory()){
					out.println(getError("上传目录不存在。"));
					return;
				}
				//检查目录写权限
				if(!uploadDir.canWrite()){
					out.println(getError("上传目录没有写权限。"));
					return;
				}

				String dirName = request.getParameter("dir");
				if (dirName == null) {
					dirName = "image";
				}
				if(!extMap.containsKey(dirName)){
					out.println(getError("目录名不正确。"));
					return;
				}
				//创建文件夹
				savePath += dirName + "/";
				saveUrl += dirName + "/";
				File saveDirFile = new File(savePath);
				if (!saveDirFile.exists()) {
					saveDirFile.mkdirs();
				}
				SimpleDateFormat sdf = new SimpleDateFormat("yyyyMMdd");
				String ymd = sdf.format(new Date());
				savePath += ymd + "/";
				saveUrl += ymd + "/";
				File dirFile = new File(savePath);
				if (!dirFile.exists()) {
					dirFile.mkdirs();
				}

				FileItemFactory factory = new DiskFileItemFactory();
				ServletFileUpload upload = new ServletFileUpload(factory);
				upload.setHeaderEncoding("UTF-8");
				List items;
				try {
					items = upload.parseRequest(request);
				
				Iterator itr = items.iterator();
				while (itr.hasNext()) {
					FileItem item = (FileItem) itr.next();
					String fileName = item.getName();
					long fileSize = item.getSize();
					if (!item.isFormField()) {
						//检查文件大小
						if(item.getSize() > maxSize){
							out.println(getError("上传文件大小超过限制。"));
							return;
						}
						//检查扩展名
						String fileExt = fileName.substring(fileName.lastIndexOf(".") + 1).toLowerCase();
						if(!Arrays.<String>asList(extMap.get(dirName).split(",")).contains(fileExt)){
							out.println(getError("上传文件扩展名是不允许的扩展名。\n只允许" + extMap.get(dirName) + "格式。"));
							return;
						}

						SimpleDateFormat df = new SimpleDateFormat("yyyyMMddHHmmss");
						String newFileName = df.format(new Date()) + "_" + new Random().nextInt(1000) + "." + fileExt;
						try{
							File uploadedFile = new File(savePath, newFileName);
							item.write(uploadedFile);
						}catch(Exception e){
							out.println(getError("上传文件失败。"));
							return;
						}

						JSONObject obj = new JSONObject();
						obj.put("error", 0);
						obj.put("url", saveUrl + newFileName);
						out.println(obj.toJSONString());
					}
				}
				} catch (FileUploadException e1) {
					// TODO Auto-generated catch block
					e1.printStackTrace();
				}
			}
	
	
	private String getError(String message) {
		JSONObject obj = new JSONObject();
		obj.put("error", 1);
		obj.put("message", message);
		return obj.toJSONString();
	}

}
